Ellery Queen Mystery Magazine, and then went on to place another hundred and fifty poems, about a third of them mystery.
A thing I like about poetry is that it allows you to focus the reader. It's like the difference between a long inconclusive fight and a sharp blade to the belly. Despite all the blows that land in a fight, the blade has more impact. With a poem, the reader is less likely to get distracted by dialogue and action and subplots. What's there is real, and it's it.